Earlier this month, while inspecting Saint Louis Harbor, Lynn Muench pointed to an abandoned hulk rising out of the parched Mississippi River and asked, “What the heck is that? It almost looks like a Burger King.” Turns out she was right: Twenty years ago, the sunken barge was a Burger King restaurant that was tied up near the Saint Louis Arch. It broke loose and sank during the flood of 1993. It disappeared under the water until this month, when the Mississippi hit near all-time lows.

There’s a lot of formerly submerged stuff poking out of the water these days, as the Mighty Mississippi increasingly takes on the characteristics of a lazy tubing venue. Just south of downtown Saint Louis is an old Navy mine sweeper. “We all knew it was there, but no one’s seen it since 1988,” says one old-timer. The summer of 1988 is the benchmark of bad droughts. “If things don’t change soon, we may get there again,” says Muench of The American Waterways Operators, the trade association for the U.S. tugboat, towboat and barge industry.

A combination of scorching temperatures and some of the driest months on record caused what experts are calling a “flash drought.” Generally, says Jim Kramper, a meteorologist at National Weather Service in Saint Louis, a drought happens slowly. “You think of things drying up over months and months, ” he says. “But we’ve really only had three months of dry weather.”

There was no sign of trouble earlier this year. “Winter and spring actually had fairly normal or even a little above normal rainfall,” Kramper says. “But all of a sudden in May, it just shut down. We had the driest May and June, combined with record temperatures. You combine those two and you’ve got trouble.”

Indeed, the Mississippi has been closed on and off for weeks now. The latest shutdown was instituted around 6 a.m. Wednesday when a grain barge ran aground 10 miles south of Vicksburg, Mississippi. It can take hours, or days, for the river to reopen. Once the grounded vessel is removed, a barge equipped with a 3-D imaging system is used to mark the river bed. Then a series of barges, starting small and working up in size, must traverse the river heading north. Once it is deemed safe for north-bound travel, the same process is repeated for south-bound vessels. Then the river can be reopened.

To make the river safer for barge travel this summer, the industry has re-calibrated capacity. Typically, barges may load to a draft of 12 feet. That’s been cut down to just 9 feet. One inch of draft generally equals about 17 tons of cargo. On top of shallower drafts, the number of barges allowed per tow has been nearly halved. Normally, a tow boat can move as many as 45 barges at a time. That’s been cut down to 20 or 30 at the most.

It isn’t just the barge industry that’s impacted. “The entire aquatic community is suffering,” says Bob Criss, professor of Earth and Planetary Science at Washington University in Saint Louis. “The heat and low levels of oxygen, not to mention the low water levels, put a lot of stress on fish,” he says. “The water gets hot.” River mussels are dying off as their cool water beds dry out in the sun, and even waterfowl can’t escape the drought. Ducks and plovers build nests on sand bars or small islands as a way of making them more secure, Criss explains. “When all of a sudden that island isn’t an island anymore, you’re at risk for getting raided by coyotes or raccoons.”

A few miles north of Saint Louis, where the Missouri River empties into the Mississippi, things aren’t much better, despite record flooding on the Missouri last year. “All that water’s gone now,” says Kramper. “And even though they are releasing from the Missouri reservoirs, there’s not as much water coming down (to the Mississippi) because there’s no input.” As of Wednesday, more than 63% of the water flowing down the Mississippi past the Arch was Missouri River water, and it’s steadily increasing as the big river’s own waters and other tributaries dry up. Back in the 1988 drought, a full 88% of the water in the Mississippi came from the Missouri. “We’re likely to get to that 88% mark or higher, if we don’t get some rain soon,” says Muench.

The Missouri in normal times drains some of the most arid parts of the country, Criss says. The drought makes it worse, despite some of the largest reservoirs in the world. “It’s an enormous watershed, but it doesn’t have a lot of water,” he says. “For a watershed of that size, it’s a pretty tiny river.” Things could get more dire if the drought continues into late fall. Water is released into the Missouri from reservoirs upstream to make it navigable only from April 1 to Dec. 1. After that, the river closes to navigation for the winter.

The outlook isn’t good. August has been cooler than normal so far, but that’s expected to change. “The long-range forecasts say we’re going to see more higher-than-normal temperatures and less-than-average rainfall on through September,” Kramper says.

A few late season rain storms haven’t done much to ameliorate the situation. “What we need is a couple of months of normal or a little above normal rainfall,” Kramper says. “Then we need normal rainfall on a regular basis through the fall and winter.” The drought can’t end in a day or even a week, he says. “That much rain all at once would mean another sort of disaster.”